Indonesia will deploy U.S.-made F-16 fighter jets to the Natuna islands to ward off “thieves”, the defense minister said less than two weeks after Chinese coast guard vessels clashed with an Indonesian boat in the area.

The move is part of a military buildup on islands overlooking the South China Sea that will see a refurbished runway and a new port constructed, Ryamizard Ryacudu said in an interview on Thursday with Bloomberg News. It also involves the deployment of marines, air force special force units, an army battalion, three frigates, a new radar system and drones, he said.

The planned stationing of five F-16s reflects a new level of Indonesian concern about territorial disputes in the South China Sea that are pitting Beijing against several of its Southeast Asian neighbors. Indonesia is not a claimant, but the clash with the Chinese coast guard last month over the detention of a Chinese fishing boat showed the potential for it to be drawn into conflict.

“Natuna is a door, if the door is not guarded then thieves will come inside,” said Ryacudu, a former army chief of staff. “There has been all this fuss because until now it has not been guarded. This is about the respect of the country.”

The minister also said he was considering introducing military conscription in Natuna and other remote areas of the 17,000-island archipelago, “so if something happens people won’t be afraid and know what to do.”

China claims more than 80 percent of the South China Sea, bringing it into dispute with Philippines, Brunei, Malaysia, Vietnam and Taiwan. Beijing’s claims, which it has been pressing more assertively in recent years, are based on a so-called nine-dash line for which it won’t give precise coordinates. In passports issued in 2012, China’s line encroached on the exclusive economic zone that Indonesia derives from the Natuna islands.

The increased proximity of Chinese fishing boats and coast guard vessels to the ships of other countries has also caused unease in Malaysia. The country’s foreign affairs ministry summoned Chinese ambassador Huang Huikang to register concern over the alleged encroachment of Chinese-flagged boats in the South China Sea, it said late Thursday.

‘Meaningless’ show

Aaron Connelly, a research fellow at the Lowy Institute for International Policy in Sydney, questioned if stationing F-16s in the Natuna area would act as much of a deterrent or be of use combating illegal fishing.

“It looks like a show of force, but it’s a meaningless one,” he said. “Indonesia has diplomatic cards to play but it doesn’t have military ones. It’s not going to scare away the Chinese military by putting a few F-16s on Natuna. These are items that can’t be reasonably used to survey maritime activities.”

Ryacudu also said he hoped to finalize a deal to buy between 8 and 10 Russian Sukhoi Su-35 fighter jets in a trip to Russia in early April. The government had been considering purchasing Lockheed Martin Corp.’s F-16V, BAE Systems Plc’s Eurofighter Typhoon or Saab AB’s Gripen.

Asked if Indonesia intended to by any F-16Vs in addition to the Su-35 jets, Ryacudu said “no, we have enough already.” Still, he said Indonesia would continue looking to various countries for procurement.

“We will buy from Europe and America, from Russia also,” he said. “We don’t prioritize. The important thing is if we need them, and the research backs it up, we will buy. We are replacing old planes, not adding new ones.”